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In this article, NVH performance of fully electric vehicles and some key technologies for NVH improvement are presented. A focus is made on a global NVH simulation methodology able to take into account the electromagnetic excitation sources and all the powertrain structure. Examples of simulation results are shown which allow us not only to predict the NVH performance, but also to understand better the fundamental NVH behavior of an electric motor. In an electric motor, the most important NVH phenomenon is the whistling noise, which is caused by the electromagnetic forces and amplified by the powertrain structure. With the current NVH simulation technology, e-motor whistling noise levels can be accurately simulated up to 4500 Hz. The improvement of e-motor whistling noise can be achieved both by reduction of the electromagnetic forces at the source and by optimization of powertrain structure.

The recent use of electric motors for vehicle propulsion has stimulated the development of numerical methodologies to predict their noise and vibration behavior. These simulations generally use models based on an ideal electric motor. But sometimes acceleration and noise measurements on electric motors show unexpected harmonics that can generate acoustic issues. These harmonics are mainly due to the deviation of the manufactured parts from the nominal dimensions of the ideal machine. The rotor eccentricities are one of these deviations with an impact on acoustics of electric motors. Thus, the measurement of the rotor eccentricity becomes relevant to understand the phenomenon, quantify the deviation and then to use this data as an input in the numerical models. An innovative measurement method of rotor eccentricities using fiber optic displacement sensors is proposed.